Instar IN-MOTION 300, Quick Installation Manual

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What is PIR?
PIR stands for Passive Infrared or Pyroelectric Infrared. PIR sensors can be defined
as detectors of warm-bodied targets in motion. A stationary target can not be de-
tected. To detect a moving target, the target must have a surface temperature that is
substantially different than the surrounding ambient temperature. Although the
usual targets of a PIR detector are warm-bodied (mammals, birds), the PIR sensor
will also detect a moving target that has a surface temperature that is significantly
lower than the ambient temperature. As long as the target is large enough, and its
surface temperature is detectably different than the ambient (higher or lower) - and
the target is moving - it can be detected by a PIR sensor.
General Considerations
Main Features:
Temperatures can often change dramatically in relatively short times. Large tem-
perature changes can render the PIR sensor either more, or less, sensitive. As am-
bient temperatures rise to near 37ºC, the difference between the target and ambient
temperature decreases - and the sensitivity of the sensor declines. As temperatures
decrease the opposite is true and the sensor becomes more sensitive.
As target and ambient temperatures become equal, the PIR sensor may no longer be
able to detect a target. Large targets usually have enough variation in their surface
temperature to allow the sensor to detect them - even when the ambient tempera-
ture is the same as their average body temperature.
The IN-Motion PIR sensors compensate the PIR detector sensitivity according to
the ambient temperature. This allows you to utilize the full range of the sensors
capabilities - whenever and wherever they are needed!
• Internal logic control to avoid false alarms
• Auto temperature compensation
• Pulse count adjustment
• White light interference compensation
• RF interference comp. (20V/m-1GHz)
• Wide angle Fresnel lense
• Ceiling installation
• Alarm output N.C. / N.O.